Kiln and the like



Feb. 17, 1931. H KRONSTAD 1,793,408

KILN AND THE LIKE Filed Jan. 9, 1950 2 Sheets-Sheet l gwuento'o Feb. 17, 1931.' H. KRONSTAD KILN AND THE LIKE Filed Jan. 9, 1930 2 Sheets-Sheet 2 m m a 7 m a 1 my I 5 x m 2 m Zlwmntoc b. ffronsfad Patented Feb; 17, 1931 jv NITED- STATES PA ENT'cFF fiA vKnn-nncnstmn, or B EssEMEn',jrENNsYLvANIA, ASSIGNOR TO min iaEs'fsnM-nit ranite conronnriojn, A coerce-Arron or 61 116 mm AND THE LIKE Application filed January 9,1930; seriar'na ua'zii';

The present invention relates to feeding material to andtre'ating it in kilns and the like and especially tosuch: devices as include a rotary cylinder in which material isto the 5 treated together .with ;a possible auxiliary treatment of the material. The character of thematerial to be introduced is not essential to the invention. may be granular, powdered, fluid, slurry or any otherform. The

lai' g'ely immaterial as far as the present invention is'ccon cerned; it may consist of heatpolishing for other treatrnent.

An embodiment of the invention has been tested applied to feeding material to a ro-. y tarykiln used for the manufacture of cement I and without indicating that the invention H0 is to be limited to such mechanism it will.

be illustrated and described with especial attentionto its use for such purpose.

The usual l gilnjnow' employed in commercial and industrial plants for the manufacture of cement consists of a long cylinder which rotates-about its axis and which is I slightly inclined to the horizontal. The inclination of the cylinder tends to feed the [material received and treated from the higher endflto the lower end; rotates itlifts material on the bottom of the cylinder and causes it to fall downward and forward. It is common in such cylinders .to-augmen't this fin-warcl movement by pro- -*5 v1d1n on the mner surface of the cylmder treatment the material is tore'c eive in the k ln or otherdevlc'e lnto which t 1s fed isv drying, calcining, clinker-1n 'IlnCl-lllg;

As the cylinder v Ordinarily in order to maintain this high temperature fuel of some sort, such as oil powdered coah, natural gas or the like, is forced into' the cylinder at its lower end andsconib'ustion takes place within the cylinder. Any other suitable means may be employed for heating the cylinder and its contents. "In-order to properly comhust"v the fuel and conduct the heatthrough thecylinderso thatrit' may come in contact with .the cement-making" material a considerable draftis necessaryor desirable and any obstruction in the cylinder which prctrudes'" into the path of the heated gases of combustion' tends to interfere with the draft and impedesthe'proper functioning-of the apparatus. p e 7 i The devices now in use; generally feed the cement-making materials into the upper end of the cylinder. A-hoppe'r or" the like is arranged above this" upper end and a more or less: inclined chute extends therefrom downwane-1a into; ween-def the cylinder thus forming an olos'tructiontojthe draft. Possibly because ofth'e'finclination, it has gen: erally been found thatmateri'z il being fed through thehopper and the chute will deg unless it. is forced downward through 'fthe chute byfsome'f such means as a screw pro peller. Suchan arrangement means ,e'nlarg; ing the chute and consequently causing it to obstruct the draft for the outgoing gases to an additional material extent. In as much; as the chute extends into the highly heatedgases, it has frequently been found desirable to cool the chute by means of'a surrounding water acket which in turn increases the size for the combustion and the outgoing gases. In order to have the outlet of the chute faralong the-axis of the cylinder as'poss'ible, the chute generally extends substantially en'- tirely across the diameter of the cylinder'f of the chute andfurtherobstructs the draft making in all' a very material obstruction to the'pas'sa'ge of" gases; Incas muchas the material at bestgby this construction, is fed to the cylinder very near'to its upper end there isa tendency for the material to pile up at that end and instead of all passing" downward through the cylinder some of it 1 may fallout of'it at the upper end; In order toavoid this'there is'generally provided at,

the upper end of the cylinder a retaining ring which is an annulus arranged throughout the circumference of the cylinder and extending inward so as to hold in any material which may accumulate at the upper end of the cylinder. This retention ringby projecting into the cylinder decreases the out-let or mouth of the cylinder and cooperates with the feeding chute to further reduce and impede the draft. n g v The materials which are to be calcined and clinkered to form cement are ordinarily ground to a more or less fine powder before they are introduced into. the'cylinder so as to make this treatmente'asier. This grinding may be done dry and so a dry powder produced. The grinding process, however, is aided and made more economical by adding water to the material so that instead of a dry powder is produced a more or less fluid mass whichis technicallyknown as soup or slurry. In'this condition the material is'easily handled and may conveniently'be fed into the cylinder for calcining and clinkering- The evaporation of the contained water, however, absorbs a "considerable amount of'the heat in the cylinder and such procedure has been 'found'uneconomical. The preferred procedure, therefore, is to effeet a preliminary drying of the slurry which generally is done by vacuum or suction process which remoyes' a large proportion of the water, leavinga sticky, past'y'inass-referred to as slurr'y cake and which when fed into the cylinder 'may be calcined and clinkered without too greatv a waste of heat for water evaporation. No, matter what is the form of the material when fed to the cylinder it is gradually dried and finally calcined and clinkered in its passage from the upper end to the loweror outlet end of the cylinder. The blast ofheated gases passing through the cylinder inevitably lifts and carries with it some of the material in the fo'rmof a'more or less fine powder and usually this powder is collected in a settling chamher at the upper end ofthe cylinder andrefed to the-kiln requiring mechanism which performs a function technically unnecessary in the calcining and clinkering operatlon.

The present lnvention is intended to overcome the objections inherent in the apparatus as above described and to accomplish the feeding and calcining and clinkering of the material in a more effective, eflicient and economical manner. 1 r

By the present inventionthe feeding mechanism is so placed that it produces no permanent obstruction within the cylinder and does not reduce or impede the draft therethrough. In addition to this, the present invention may tend to collect and keep in the cylinder any powder or dust carried by the blast of the heated gases thus possibly to an extent doing away with the necessity for the auxiliary dust-feeding apparatus. The arrangement 7 may eflecta desirable treatment of the material fed.

While the feeding mechanism of the present invention is adapted to material ground may be fed by any suitable means the prepared material to be fed'to the kiln. i Such a hop-' per or receptacle willpreferably be arranged above the kiln so that material fed into it may fall by gravity into the kiln although when desired there may be employed any well known screw-feeding device or. other means for forcing the material from the hopper into therkiln. The open end of the hopperaway from the kiln, when desired, may be closed or sealed; The open or outlet end of the hopper may rest directly upon the kiln or may be'connected thereto by means of a flue or other suitable conduit. Below the opening of the hopper the rotating cylinder may be provided with a series of openings :which as the hopper rotates will in succession come under the hopper so that material therefrom will fall through the, openings in the cylinder. Preferably these openings are arranged diagonally to their pathcof travel and so close together in the cylinder shell that there will, always be one or parts of two or more openings directly under the open end of the hopper so that material passing through the hopper may always be fed directly into the cylinder. Associated with the, openings on the strips of'shell between themor on the portion surrounding them or, on both may be arranged cleats orvanes, possibly in thev form of angle irons, to collect and, deliver intothe openings material falling from the hopper on the portion of the shells surrounding the openings. These surrounding vanes may be arranged at appropriate anglesrso that as the cylinder rotates they may force the entrapped material, urged by gravity, into and through the openings into the cylinder.

Material thus falling through the cylinder will tend to form a more or less complete pervious curtain across the area of the cylinder with out materially impeding the draft and, especially if in the form of slurry or slurry cake, will tend to collect from the gases the entrained dust and retain it in the cylinder. Because of the inclination of the cylinder the holes in their travel across the bottom of the apparatusmay not be directly and stirring up the material where gr1nd-, -mg ordrying may be part of the process being performed, or inpolishing where such,

5?: fectively regulate the draft and prevent exu dation of material at the outer side of the .on the line H ofFig. Fig. -5 tailed view partially in section showing'the rotate upon bearings indicated at 9.

means for rotating the cylinder may be of j under the receiving openings in'the top portion of the shell but will be somewhat above them. 1 The tendenc therefore, of the en tering material will e to fall on the interior of the cylinder toward the lower end thereof. It may happen, nevertheless, that some of the material may fall through the openings at It may be desir- Y the bottom of the cylinder. able, therefore, to provide a casing connected with the outlet of the hopper and-entirely: surrounding the cylinder and covering the holes therein to catch any material passing out of the holes at the bottom of their travel so that the vanes or angle irons carried by the cylinder may collect materialat the bottom 'ofthe casing and carry it upward as the cylinder rotates until gravity draws it into isa function-of the apparatus.

In order to conserve the heat and more efe casing means may be provided for effecting a' seal between the casing, the hopper and the rotating cylinder.

. In the accompanying drawings Figure 1' is a side'elevation of ak-iln and charging device embodying thepresent invention. Fig. 2 is asimilar side elevation of a portion of the apparatus on an enlarged scale and partly 'brokenaway so as to show additional portions of the mechanism. Fig; vertical section of the'line of Fig.2. Fig, 1- is a similar transverse vertical section is a deseal for the casing. V g r The apparatus consists of a main, rotary cylinder 8 which may be of any suitable dimensions and which is carried so that it may any suitable form and are not illustrated as such devices are well known 1n the art.

cined or clinkered material maybe removed. Fuel or heated gases may be introduced n 7 any suitable well known way. Throughthechamber 10 and possibly entering the cylin der 8 may be a pipe or other conduit 11 through which fuel may be introduced into the cylinder 8 to heat and eventuallycalcine and clinker the materials which combine to makecement. "At the otheror upper end of 3 is a transverse The At the lower end ofthe cylinder is the usual; outlet chamber '10 through which the calthe cylinder 8 may be provided a dust ch'aniher 12Iconnected with the stack orchimney,

not shown. 3111 ordinary course the products of combustion of the fuel willfpass through the cylinder and up the. chimney. If any ce ment or cement-making material or other I dust is carried by the draft beyond the upperend of the rotary cylinder S it may be entrained or collected .by anysuitableor well known means in the chamber 12 and discard ed or again fed into the rotary cylinder.

When working with materials which have been'g r-oundwet the slurry with itsjhigh water 'contentmay be fedby any suitable means, not 'showmon to a traveling belt car rier 3 which 'may be operated'by any suit able or well known mechanism: While .on v

the conveyor belt the wet slurry may be operated 011 by the usual vacuum or other. apparatus, not illustrated, torem-ove the clesired amount of water. Any other suitable means may be employed) to pretreat the ground materials but this forms no part of the present invention. The partially dried slurry cake may then be fed by the conveyor belt 13 to the clinder or intothe hopper 14.

Wdhere the conveyer. belt 13 joins the' hopper it maybe covered by an enclosinghood 15 of any suitable material forming a seal; That portion of the shell of the cylindery8 which 3 lies immediately under the hopper 14 maybe provided witha series offholes or openings 16 givingaccess to the interior of the cylinder 8. The holes 16 will bearranged'preferably in a band around the cylinder so that as it rotatesthe holes preferably at the topmost point of their travel will come one after the other directly under the outlet or bottom of the hopper 14 As shown, the width of the v i V I holes in a direction parallel to the axis of. the cylinder is somewhat greater than the width of the opening of the hopper 14; y This arrangement is preferred but'is not essential to the invention. of course it-is' clear thatthere may be very little tendencyfor material coming from the hopper to accumulate on the shell of the cylinder 8 at thesides of the holes 'for the rea-' son that the spread of'the material as it leaves the hopper 14 may not he further than the sides. of the holes 16. r

The portions'of the shell of the cylinder 8.

which intervene between the holes 16 are shown at 17 as being mater ally less in area than the holes 16 and this is a preferable ar- With this arrangement rangement but not essential to the invention.

The intervening strip .17 may profitably 'be as narrow as possible, while still retaining the necessary strength to. avoid rupture or dissolution'of the shell. It is obvious that opportunity for material coming from the hopper 14 to lodge on the strip 17 is, reduced.

The edges. of the strips 17 formend walls to the holes 16 andare inclined at an angle to @125, by reducing the area of the section 17' the the line of their circumferential travel and;

an effect of this is to cause the edge of the strip- 17 tohave 'a shearing actionupon the material fed fromthe hopper 14. Likewise by this inclined arrangement or the narrow separating-strips or both generally portions of more than one oftheholes 16 will underlie the openingof the hopper 14 so that there will be two directions that material. on a strip 17 and coming from the hopper 'may fall.

This materially. reduced the chance of'mashown on each of the strips l7and they are arranged so that'their operating faces are substantially at right angles to their line of travel and they are-staggered so that the four ironson any one strip together will cause a. clean sweep of the bottom'of the hopper 14" .in their passage therethrough. As each strip 17 passes under the hopper 1& some material will be delivered on to it. Some of this will fall into theicylinder through adjacent holes 16; The material that remains on the strip 17 may be caught by the angle irons 18 and carried forward until as the cylinder 8 turns about its axis the material will fall by gravity into'an adjacent opening16. r

In order to further insure complete feeding of the material fed in from the hopper 14 angularly disposed vanes 19, taking the form of angle irons in the drawing, may be arranged on the shell 8 'at the sides of the openings 16. The vanes 19 will tend to entrain any material which'may fall beyond the sides of the holes 16 and carry and divert it until gravity causes it to fall along the incline of the vanes 19 into an adjacent opening 16. By this arrangement material may be surely and positively fed from the hopper 14; into the interior of the cylinder 8. Since the material in the hopper 14 has a verticalm'ovement its advance may generally be insured by gravity alone but when desired suitable force-feeding mechanism may be employed in the hopper 14.

While a hopper has been described it may be replaced by any suitable or convenient collecting or feeding arrangement or itmay be omitted entirely and material admitted directly from the'conveyer 13 to the cylinder or it may be deliv'eredin' any other way and the term hopper as used in'the claims is intended to include'any device for delivering material tothe-cylinder. j

Connected with the mouth of the hopper 14 is a casing 20 which surrounds and encloses the cylinden8and is-s'paced far enoughthere from to not bind against the vanes 18 and 19. It is desirable that there be provided a seal betweenthis casing and the cylinder. As shown in'Fig. 5 the casing has an annular flange or edge 21 whichis turned inwardly and extendstoward the shell of the" cylinder 8. An annular ring 22 surroundsthe eyli-nder8 and is; free to slide long-it'udi nally; thereon. A series of lugs 23- risingfrom the'sh'ell of the cylinder 8,carryb0lts 24; extending intothe annulus 22; Surrounding thebolts 24 and lying between the lugs '23- and the annulus 22' are coil springs" 25' which keep the annulus 22 inclos'e'contact with the annular edge 21 of the casing 20 and thereby form a seal. Any other suitable seal may be used.

The material in the cylinder may be fed forward toward the right of F igsgl and 2 in the outlet chamber 10'of the cylinder. These r vanes may extend from the inlet end of the cylinder past the openings 16 and-any suitable distance therebeyond as is well known in the art and so movezforward "substantially all of the material fed'into the cylinder.

The holes 1621s they travel about the cylinder, however, reach its lower portion and any material directly above the .holes will of course have a tendency to fallout and into the bottom part of the casing 20. It will be remembered that the cylinder 8 as usually used'in theart maybe inclined so that the portion shown at the left of Fig. 2 is higher than the portion shown at the right of that figure. The result of this is that any ma terial falling vertically from the hopper 1% into the cylinder 1 may tend to fall not through a hole '16'at-the bottom but on to a portion of the cylinder at the right thereof as shown in Fig. 2 so that a relatively small portion of the material may find its'way into the bottom of the casing 20. Whatever material does reach the bottom of the casing 20, however, may be engaged by the vanes- 18 and 19 as they move with the rotating cylinder. The material so engaged will be lifted and carried'np upon the vanes 18 and 19 orrol'l'ed between them and the casing until they reach such a position that the an-' gular arrangement of the vanes will allow the material to be forced by'gravit'y into the cylinder 8 through directly adjacent openings 16. This intermediate manipulation of the material'may be an advantage in some proceedings V The vanes have been illustrated inclined as is most expedient when-the cylinder rotates so'that the holes visible on the front of" thev 't'erial will form a'curtain covering more or rupting theoperation and causing delays no less the entirecross-section ofthe cylinder. The cool entering material especially if somewhat moist as slurry cake, when it meets the 'heated gases'passing through the cylinderwill have a tendency to. extract therefrom any loose dustentrained and carried'thereby so that-with this arrangement there may be aminimum amount of dustcto be collected in the settling chamber 12.

It has been demonstrated in actual operative practice that with this device the stifi 'slurryjcake can be fed continuously into the kiln without danger of packing or intermatter what the stage of drying or exhaustion of the water in the slurry cake may be. The 2clevicewill rake it-up and carry it back to'the openings continuously. Incidentally thedevice expedites the breaking oup 0f the slurry cake and its assembly into alls in the I cylinder in which form it may be acted upon most advantageously by the heated gases. more or less similar advantageous manipulation of the fed material may take place no ments which separately consideredmay be matter what is its character. 35

As stated, the apparatus is adapted in ad dition tolmere feeding to the cylinder, to the polishing of material polished by rotation and shaking either alone or in connection with the lnclus onof grinding or pol sh ng materials such as balls or otherwise; and to I thejgrinding and mixing of materialswhen no other treatment is required.

,V' hile the apparatus illustrated inl the drawingshas been" described as one embodi mentor the invention it will beunderstood :that it is done for the purposeotillustration only? .The Y invention is not confined, to the 1 details of; structure or assembly or relative prbpb ion io l p rp s of he o el gmentsasfshQWnv. but may be embodiedin many diverse forms of apparatus using 'eleold andwelll knownfi Some arrangements maybe lessefficient than the present arrange ts ut may .stillembody the invention'or .1 chimes m invention; g

In: o h like-a h re gaeh fder' retating under the hopper and provided 1 a tpermre adapted to pass under the hopper as the cylinder rotates end wallslfor the apertur ar ange at an angle, diagonal to'the path oftravehand meanspadj acent the I apertureito collect, and .feedby grtn'rity addi- 65.

tional matter comin from the hop er. a

.' 7 ,In a kiln or the'like a hoppe rotating under the hopper and provided with a an aperture adapted topass under the hopper as the cylinder rotatesend walls for the aper- 2 In a or the like a hopper, a rotary cylinder under the hopper and provided with an aperture adapted to pass under thehopper as the-cylinder rotates, end walls for the aperturearranged at an angle diagonal to the path of trave'l',..means adjacent the aperture to collect and feed by gravity additional matter fromthe hopper, and a, seal for.- the hopperan'd aperturel 8. Ina kiln orthe like a'hoppjer, a seal-for the hopper, a Tlcylinder rotating under the hopper and provided" with 1 a: series of aper: tures in a. band adapted to pass under the the apertures arranged at an angle diagonal to their path of travel underthe hopper,

means between'the apertures to receivekinaterial from'vthe hopper and carry it andto deliverlitthrough the apertures and a seal for the hopper and the apertures.

e. In a kiln or the like a hopper, a seal for the hopper, a cylinder rotating under the hopper and provided with a series of apertures in faband' adapted to pass under the hopper as the cylinder rotates, end WElllS for] the apertures arranged at an angleldiagonal to theirpath of travel'under the hopper, means between the apertures to receive, material fromthehopper and carry it to deliver it through the apertures and a seal surround- -hopper'as thecyli'n'd'er' rotates, end wallsjfor ing the cylinder and engaging the hopper 5'. In" a kiln or the like a l1opper,'a seal for the hopper,-a'c ylinder rotating directly under the'hopper. and provided with aseries of aperturesin a band adapted to pass under the hopper as the cylinder rotates, and means betweenthe apertures to receive material through theap'ertures. V

6. In a kilnor the like a hopper,,acylinder rotating under the hopper and provided with an aperture adaptedto pass under the hopper'as the cylinder rotatesand allow matter 'ter coming. from the hopper. f

from the hopper and carry to deliver it ,7

to drop directly into thelcylinder ,from the hopper, and means adjacent the aperture to collect and feedbyI-gravity additional mat r, a cylinder.

ture arranged at an angle diagonalto, the

path of travel, means adjacent the aperture to collect and feedby' gr'avity additional; 7

matter coming from the hoppergga stationary band for the lhopperlfand aperture, and-resih ient meanscarriedby' the cylind r a den gagingthe band to iorrnia seat: 1

able cylinder having a series of holes'circumferentially arranged ,iin its shelh} diagonally arranged vanes on the shell between the holes, vanes on the shellatthe sides of-the-hol'es arranged at an opposite .aiigle'tothe first men- .t lOllGdlVitIlGS, a 'stat enary hopper arranged s." In eannette like, an. mclined-rdtat 7i 1 andfe'd into the cylinder through the holes.

j 9. In akiln or the like, an inclined rotate able cylinder having-a series of holes circumferentially arranged in its shell such holes having sides at an angle diagonal to, the axis of the cylinder, diagonally disposed projections on the shell between the'holcs, pro? jections on the shell at the sides of the holes arranged at an angle obtuse to that of the disposition of the first mentioned projections,

a stationary hopper arranged'above the cylinder and in line with the holes a statioi'iary casing surrounding the cylinder and cover: ing the holes and projections and engaging the hopper, and means to rotate the cylinder to cause material in the hopper .to entcrthe cylinder through the holesfland additional materialto becaught by the projections and I -fed into the cylinder through the holes.- 7

'10. In a kiln or the like, an inclined rotat;

. able cylinder having seriesno f holes in its shell, projections on the shell between the holes, pro ections on the-shell at the sides of the holes, a hopper directly ahoyethe cylinder and inline with the holes, a casing sur;-

' rounding the cylinder and-covering the holes 7 th ough h hole and add ion materi l and projections and engaging the hopper, and means to rotate the' cylinder to cause material in the hopper to {enter thecylinder from the hopper to be canght by thefprojece tions and fed into the cylinderthroughthe hol s, and addi i na material iathelcasig' to be caught by the projectionsand fed into he cy i d r through the hQ1esj 5 11. In a kiln or the likea rotary cylinder having a series ofspaeed openings arranged diagonally withrespect to their line of travel anda hopper arranged ahovc' lifi Cylinder so thatais the cylinder rotates there is always an I ."i n nin ohe. cy n r b ow he h pp r- 12,"kiln or the-like rotary cylinder having riesgc neccdfl p n ng s arr ng d diagonallywith respecttot irelinegl trayel, a hopper arranged above the l' nder so that the cylinder-i rotates there is always an,

op i es nto e yl ndeiibelw th beep intermediate strlps between the openings, nd rncansoathe trip to e dmater al into the openings as the cylinder rotates,

13, In a kiln or the like, means for feeding material thereto, a rotary cylinder havinga series of aligned circumferential openings .of such arrangement and so' spacedfthat some part of one or more openings will atall pea,- riods of rotation lie in line withthe said means for feeding material through such pe ng n o th yl l e e an n sealed ca ing enclosinga portion of the cylinder adapt: ed tor retain material which might pass out: war'dly from the cylinder throngh the open,- ings into the casing, and toprevent the pas.-

sa'geof materials or gases outwardly from.

between the-casing and the cylinder and inwardly, and means onwthe onter CII'QLLIII? 'ference of the cylinder between and adj aeent t t f pe ng adapte t .delirer to the openings fed material not directly-enter? ing the cylinder or passing through the open? ings into the space between the cylinder and the casing. I i l v i 14.. In a' kiln or. the like, means. tor feeding .nm a th a y cylinder having-a Series of aligned circumferential open ngs of such arrangementgand so spaced'that some part of one or more openings will at all p,e..- riods vof rotation lie in line with the shid means for feeding; material lthrough such e ni g i th cylind r; an en sea ed ing enclosinga portiono f the cylinder adaptd a o e ain .vm t r a wh c mig t pa slatmay f om he i y nde hm gh he-ar n'- sage of materials or gases .ontwwdly from betwee t e a ins'and t yl nd aada r inwardly, and meanson the outer cireurn-' ,iielell e of t e ylind r between and adja cent-to "the feed openings adapted'to deliver to the openings fed material not directly enteringthe cylinder or passing through the sp l in nt he sp f w.e mv he ylilr der and the casing and to nizg, grind OI-IlbllSh in addition tothe action within the cylinder itselt' 1 In a kil r theli ea-h ppee a ylin t ing un t h pper nd provided withflapertures adapted to pass under th h pper a ef ylinderre a e the majier di n n. of th ap rture arrange at a g e diagona wastes of he ylincler, an m an a ja nt th a ertu es t tal; l nt a d fee nt th y in er byg avity matter; coming. from the hopper an'dfnot, dilr yr ss n thro g he ap rtur s,

v In a; ki n orth l ke'a n lined rotat a l cy in h ng-ase ies' of ho s. c rcumdisposedvanes on the shell betweenthe holes,

, ne th hel at e id s Inf he 9 o -at mang o tu he that of th p sit o o t firs'tmeatined vanesa ti y hoppe mane-ed a o theieyliarings into the casing, and to prevent the pasde nd line w th he. hol s, tat onary ing the ho e a r tes and enga ing h pp ta' nsi means o create thejcylinderto eas ng sur u d ng he eylinder and cc et r material between the Cyllllderjand'the c asll g 22 'fer'e ntially arranged in its shell, diagonally cause material in the hopper to enter the cylinder through the holes and to cause additional material from the hopper to be caught 7 by the vanes and fed into the cylinder through the holes. 7

17. In a kiln or the like, a hopper, a rotary cylinder having a series of openings so spaced and arranged diagonally to the line of rotation that as the cylinder rotates there is always an opening or parts of one or more openings into the cylinder directly below the hopper.

18. In a kiln or the like, a hopperarranged I I above a rotary cylinder having a series of openings so spaced and arranged diagonally to the line of rotation that as the cylinder rotates there is always an opening or parts of one or more openings into the cylinder directly below the hopper, intermediate strips between the openings, and means on or adj acent to the strips to feed into the openings as the cylinder rotates material from the hopper which does not pass directly through the openings. r

19. In a kiln or the like, a rotary cylinder,

gravity means for feeding material thereto,

a series of spaced openings in the cylinder,

the spaced openings being so arranged that as the cylinder rotates there is always an opening in the cylinder adjacent to the feeding means so that there is a continuous-entry of materlal into the cyllnder, and means ada jacent to the openings to feed into the cylin- 'der as it rotates material not passing directly through the openings. V

20. In a kiln or the like, a rotary cylinder, means'for feeding material thereto, a series of spaced openings in the cylinder so ar-' ranged that as the-cylinder rotates there is always an opening into the cylinder adjacent the feeding means so that there is a continuous entry of material into the cy1in-. der and means on the cylinder adjacent the openings to feed material thereinto as the cylinder rotates.

' HAAVARD .KRONSTAD.

'ln'of- 

